code for diagram
>
mat:=matrix(2,2,[seq(plot({x^i,i*x^(i-1)},
x=-1.2..1.2),i=1..4)]):
> plots[display](mat,xtickmarks=[],ytickmarks=[]);
>
mat2:=matrix(2,2,[seq(plot({-x^i,-i*x^(i-1)},
x=-1.2..1.2),i=1..4)]):
> plots[display](mat2,xtickmarks=[],ytickmarks=[]);
>